Hello everyone,

If you've followed any of my other threads you'll know that I've been having issues with my carburetor. Well, I've finally decided to bite the bullet and buy a new carb. Since I'm not too savvy regarding carburetors I would like some advice on which to get. I'm currently looking at either the Edelbrock 1405 or 1407 carb. I had a couple of questions of course.

1. Would a 600cfm carb be adequate for a 460 engine? I'm only going to be towing the race car with the truck. A total of 12,000 lbs at the most.

2. I have the Edelbrock performer intake with the EGR blocked off. Would anyone know which vacuum ports go to which part of the engine? The big one in the middle goes to the PCV. But where do the others go?



3. I am interested in having a carb that I can pretty much bolt on and go. I've heard Edelbrock pretty much meets or exceeds this expectation. Is this true or is there a better carb out there?

I know that this question has been answered time and time again but i couldn't find any definitive answers when I did my search. Sorry for any redundancy.

 

1. 600 CFM is enough, and is commonly used.

2. The big middle port is the PCV line as you mentioned. The one to the right is manifold vacuum, the one to the left is ported vacuum.

3. I too, have heard many people say Edlebrocks are "bolt on and go." I had a Holley 4180 that was having problems and wanted to end it. I was a bit worried that the new Holley wouldn't fix all of my problems. I bought the Holley anyway and it is great. It fixed my idle and hesitation issues. All I did was adjust the idle mixture screws and the choke. I purchased the 80457S, which is a 4160 with the prevision for the Ford kickdown. However, I still had to purchase the spring and perch kit. Holley part # 20-60.

I bought the carb for about $292 shipped from Summit Racing. Later I found out that my local autozone had them on the shelf for $199. I just rechecked and they raised the price to $249

 

OK. Good food for thought. I don't have to worry about the kick down as I have a manual trans. The good thing about the aftermarket holley's is that the mixture screws are SO much easier to adjust. The 4180 wasn't meant to be adjustable and so the mixture screws are a PITA to get to. You almost have to remove the carb to get to them.

 

Thank you Sw1tchfoot for your advice. I decided to go with the Edelbrock. I have the intake, why not the carburetor too. I got the Edelbrock 1406. I should get it next week sometime. I'll keep you guys up to date on the progress. Thanks again.

 

I was going to suggest the 1406, which is what I have on the shelf and is slated for Dad's 351M. IIRC, the diff between 1405 and 1406 is the latter is jetted 2% leaner.

Hope you did get the Ford linkage awa the electric choke options.

These carbs are favorites of mine due to their simplicity and ease of working on. Further, once set properly they don't need much attention because they don't have things that blow or gaskets to leak gas. However, for those of us that like to tinker the Thunder series, which is an Air Valve Secondary (AVS) Carter is slightly better since the secondary is adjustable for when it opens. The AFB/Performer is adjustable one way, sooner on opening, as you have to grind material off the weight. (Bruno - does this sound like the same thing you heard last night?)

Bottom Line: Good choice.

 

Huh. So, what happens if you grind too much off the weight? Should I be pretty close to operating configuration when it comes to me? I just want to be able to start the truck and go and not mess with the choke every time. Here are the specs for the 1406 vs 1405.

1406:

Metering Jets - Primary .113, Secondary .107; Metering Rods - .071 x .047; Step-Up Spring - orange (5" Hg).

1406:

Calibrated 2% leaner than #1405. Includes both timed and full vacuum ports for ignition advance. Comes with: Metering Jets - Primary .098, Secondary .095; Metering Rods - .075 x .047; Step-Up Spring - yellow (4" Hg).

1405:

Comes with: Metering Jets - Primary .100, Secondary .095; Metering Rods - .070 x .047; Step-Up Spring - orange (5" Hg).

Right now I'm running way too rich so leaner may be the way to go. I'm very new to tuning carbs. For example, what is the difference between ported and full vacuum?

 

Gary,

You said:

I have a manual transmission. What else will I need to get for this to operate with my truck?

Something like this:

Ball End Stud - Holley Carbs 8016

 

Yes, the ball-end stud is for the Ford linkage. And, since you don't have an auto you don't need the rest of the Ford linkage as you don't need the kick-down lever.

You won't be grinding on the weights as that's for those who are looking for the last little bit of acceleration, as in racing. But, to answer the question, if you grind off too much you'll have a bog when the secondaries open too soon, so you have to add some weight back.

It should work very well right out of the box. You should be able to bolt it on and go.

 

Awesome Gary. That's what I wanted to hear. This is not, by any stretch of the imagination, a truck that will "get up and go" but will tow your house down the road if my road tests are any indication. Now to wait the week to ten days to get the carb. I opted for the free shipping...

 

600 CFM is too small. You will be leaving power on the table even with a stock 460, and you aren't gaining any efficiency by going with an undersized carb. If you tow, you will notice the lack of power and possibly hurt MPG by going too small. You should be looking around 750+ CFM for a stock-mild 460, 750 would be adequate and a good fit for a stock engine. With 600 CFM, you will be disappointed.

Aside from that, I would not run an Edelbrock. I don't like AFB style carbs. They are a lot more complex to tune due to the metering rod + jet design and vacuum secondaries don't give very positive control over the airflow and require tuning for that too. Holley is more simple and straightforward to tune. I would recommend a 750-800 CFM 4150 style double pumper for your application.

This is coming from someone who ran a 600 on a mild 460 and changed a year later to a 750. Difference was night and day all across the power band. Also note I have a similar truck, an '86 Supercab which weighs 6000 lbs on the scale and tow a 5500+ lbs trailer. Highlway MPG is 10.8 towing, though I have made some timing adjustments since my last highway tow so I expect nearly 1 MPG improvement over that. Keep in mind my truck is lifted 4" on 35" tires so that hurts my MPG significantly.

 

Seeing as the stock Holley 4180 is a 600cfm carburetor I will go ahead and try the Edelbrock 1406. If I don't like it, I can always buy the Holley 4160. I don't think I'll go to a double pumper. Besides, I've already ordered the Edelbrock.

 

Cadunkle - We could get into a here, 'cause with the exception of CFM I'm on the absolute opposite side of the fence re Holley, or Autolite-by-Holley, vs essentially any other carb. We're into the love/hate area and each of us have our experiences and reasons to draw upon. But, I won't go there as there are many on this forum whose experience and knowledge I am in awe of, yourself included, that swear by Holley's. As for me and my house, we swear at them.

Lavatan - That's a reasonable approach and I'm confident it'll work for you. However, if Cadunkle is correct on the CFM then you will experience a falling off in power as you try to wind that 460 up. On the other hand, your cam is a low RPM unit and you shouldn't need to wind the engine up.

I'm sure Cadunkle and I, along with the rest of the FTE community will be awaiting your results.

 

I guess all I can say is, we shall see. Unfortunately I don't have the money to give this a good objective test by swapping out carbs... If I did, I so would give my input on both new Holley carbs (both 600 and 750cfm) and new Edelbrock carbs (600 vs 750) and then compare all the results. So, if you know someone that has about $1000 so I can buy the other three carbs I'm afraid the shall continue.

 

I'd be happy to have a friendly debate about the merits of each carb. I think it could be beneficial to others making this decision to make it on facts and data instead of only emotions and unbacked opinion. It could help others avoid making a similar mistake as to what lavatan has made, at least on undersizing the carb. Even a 750 CFM AVS/Thunder would be a better match to this engine. With some tuning I'm sure the 600 CFM will work alright, but power and economy will be left on the table. Regardless, I'll leave that to you, if you'd like to outline why you believe Edelbrock/AFB is superior and lay out some of the problems you have had with Holley carbs.

As for the power down low, speaking from my experience going from a 600 CFM 4160 vacuum secondary to a 750 CFM 4150 double pumper I saw a noticeable increase in lower RPM power. Specifically, I did not have to downshift in low speed situations where I previously had to drop down a gear. I drive my truck like a diesel, it rarely sees the high side of 2000 RPM and has all the torque I need down low. There was of course a larger difference in power at higher RPM up towards 4000-6500. It was noticeable across the board.

 

The title of the thread is New Carb, so maybe this isn't a hijack.

I don't really have that much input on CFM, and will bow to Cadunkle's experience on his 460.

Having said that, my issues with Holley's, or Holley-designed/built Autolites, have to do with what I consider poor engineering in three areas:

• Power Valve: How many times on here have we seen people complain about blown power valves? Lots! I, too, have had the same problem many times over. But basically none of the other carbs we discuss on here have that problem-prone method of fuel enrichment, having gone to metering rods many, many years ago - and that includes the 2150. Metering rods don't blow and they and/or their springs are easily swapped by pulling the top which, by the way, doesn't spill gas all over the engine when you pull it. And, I realize it is possible to add a check valve to prevent the power valve from blowing, but that is an after-market fix to a well-know engineering problem.
• Accelerator Pump: Yes, all automotive carbs need an accelerator pump, but a diaphragm pump like Holley as chosen for most of their carbs is another problem waiting to happen. How many times have I had to pull the carb to tighten the screws because they backed out and it is leaking, or to replace the diaphragm because it split!? The piston-style pump that the other manufacturers went to long ago may wear and slowly lose its volume, but they don't fail catastrophically.
• Bowl Gaskets: I've had the gaskets leak - both from warped carb bodies as well as from the gas in the bowl going away (power valve!), and then they shrink and leak seriously. And, when you do want to change something in the carb, like the inevitable part replacement or tuning, you'll spill gas all over the manifold. No one else builds a carb that way as they use a metal casting to hold the gas in.

I consider the Holleys an antiquated design with serious problems that others solved long ago. Yes, they can be made to work well as they are tunable like all the other carbs. But, I believe the ability to change out metering rods and springs on top of the jets provides more control than Holley provides with power valve and jets.